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arXiv · 0808.2400

Phonon distributions of a single bath mode coupled to a quantum dot

F. Cavaliere·G. Piovano·E. Paladino·M. Sassetti
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Abstract

The properties of an unconventional, single mode phonon bath coupled to a quantum dot, are investigated within the rotating wave approximation. The electron current through the dot induces an out of equilibrium bath, with a phonon distribution qualitatively different from the thermal one. In selected transport regimes, such a distribution is characterized by a peculiar selective population of few phonon modes and can exhibit a sub-Poissonian behavior. It is shown that such a sub-Poissonian behavior is favored by a double occupancy of the dot. The crossover from a unequilibrated to a conventional thermal bath is explored, and the limitations of the rotating wave approximation are discussed.

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F. Cavaliere, G. Piovano, E. Paladino, M. Sassetti. 2008-08-18. Phonon distributions of a single bath mode coupled to a quantum dot. https://doi.org/10.1088/1367-2630%2F10%2F11%2F115004

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